i have try to fix problem of post back making a new file generic.browser.

making a file named generic.browser as follow and put in the App_Browser folder

<browsers>
<browser id="IE11" parentID="Mozilla">
<identification>
    <userAgent match="Trident/(?'layoutVersion'[7-9]|0*[1-9]\d+)(\.\d+)?;(.*;)?\s*rv:(?'version'(?'major'\d+)(\.(?'minor'\d+)))" />
    <userAgent nonMatch="IEMobile" />
    <userAgent nonMatch="MSIE" />
</identification>   
<capabilities>
    <capability name="browser"              value="IE" />
    <capability name="layoutEngine"         value="Trident" />
    <capability name="layoutEngineVersion"  value="${layoutVersion}" />
    <capability name="extra"                value="${extra}" />
    <capability name="isColor"              value="true" />
    <capability name="majorversion"         value="${major}" />
    <capability name="minorversion"         value="${minor}" />
    <capability name="screenBitDepth"       value="8" />
    <capability name="type"                 value="IE${major}" />
    <capability name="version"              value="${version}" />
    <capability name="ecmascriptversion"    value="3.0" />
    <capability name="jscriptversion"                       value="6.0" />
    <capability name="javascript"           value="true" />
    <capability name="javascriptversion"    value="1.5" />
    <capability name="msdomversion"         value="${majorversion}.${minorversion}" />
    <capability name="w3cdomversion"        value="1.0" />
    <capability name="ExchangeOmaSupported" value="true" />
    <capability name="activexcontrols"      value="true" />
    <capability name="backgroundsounds"     value="true" />
    <capability name="cookies"              value="true" />
    <capability name="frames"               value="true" />
    <capability name="javaapplets"          value="true" />
    <capability name="supportsCallback"     value="true" />
    <capability name="supportsFileUpload"   value="true" />
    <capability name="supportsMultilineTextBoxDisplay" value="true" />
    <capability name="supportsMaintainScrollPositionOnPostback" value="true" />
    <capability name="supportsVCard"        value="true" />
    <capability name="supportsXmlHttp"      value="true" />
    <capability name="tables"               value="true" />
    <capability name="supportsAccessKeyAttribute"    value="true" />
    <capability name="tagwriter"            value="System.Web.UI.HtmlTextWriter" />
    <capability name="vbscript"             value="true" />
</capabilities>
</browser>
</browsers>